Method for introducer replacement

ABSTRACT

The invention provides a method for replacing a first introducer, whose distal end is inside a vessel and whose proximal end is outside the skin of a patient, with a second introducer. The method comprises the steps of inserting a guide rod into the first introducer, removing the first introducer, passing the second introducer over the guide rod, and removing the guide rod. The guide rod to be used according to the method has preferably a flexible distal portion with a blunt distal end and a stiff proximal portion with a tapered proximal end.

FIELD OF THE INVENTION

[0001] The present invention relates generally to a method for replacingan introducer, which is inserted in a vessel, with another introducer,and more particularly to a method for replacing an introducer withanother introducer without the conventional use of a guide wire and adilator.

BACKGROUND OF THE INVENTION

[0002] In U.S. Pat. No. 6,090,130, which is assigned to Kensey NashCorporation, a system for sealing a percutaneous puncture in a bloodvessel is disclosed. For the determination of the position of the bloodvessel, the system comprises a blood vessel locator, which, in turn,comprises an introducer sheath and a dilator. The position of the bloodvessel is determined by observing a flow of blood out from a hole in theproximal end of the introducer sheath. The hole in the proximal end ofthe introducer sheath is via a canal in fluid communication with a holein the distal end of the vessel locator. U.S. Pat. No. 6,090,130discloses several different embodiments of how this canal and the distalhole can be arranged. A common requirement for these embodiments is,however, that the length of the dilator is adapted to the length of theintroducer sheath.

[0003] U.S. Pat. No. 6,090,130 describes also a typical, conventional,intravascular surgical procedure, in which an introducer sheathaccording to the patent can be used. It is said that in such aprocedure, a cannula of an instrument, such as an angiographic needle,is inserted percutaneously through the skin into the artery, such as thefemoral artery, at the situs for the instrument's insertion. The needlecannula is held in place and the flexible end of a mini-guidewire isthen passed through the cannula into the artery to the desired length.Once the mini-guide is in place, the needle cannula is removed, leavingthe guidewire in place. An introducer sheath and an arterial dilator arethen passed over the guidewire, through the puncture or incision andinto the artery. The guidewire and then the dilator are removed, leavingthe introducer sheath in place. A catheter, or other intravascularinstrument, is then inserted through the introducer sheath and threadeddown the artery to the desired intravascular location.

[0004] In the above description of the intravascular surgical procedure,which is taken directly from U.S. Pat. No. 6,090,130 and which is basedon the so-called Seldinger technique, it is explicitly assumed (byreference numerals) that the introducer sheath being used during theintravascular procedure is the same introducer sheath as the introducersheath into which a dilator is inserted when the intravascular operationhas been completed and the sealing operation is to be performed. Inother words, it is assumed that there is only one introducer sheath usedduring the whole medical operation, i.e. during both the actualintravascular procedure and the subsequent sealing operation. Althoughthis could be the case, it is to the best of the present applicants'knowledge almost never actually the case. The reason for this is mainlythat the needle cannula, introducer sheath, dilator, guide wire andcatheter, and possibly some more instruments, come together in aseparate set, which presumably is provided by another company than thecompany that provides the sealing system, i.e. in this particularexample the Kensey Nash Corporation. Now, if the length of the specialdilator, which is used to provide the canal in the vessel locatoraccording to U.S. Pat. No. 6,090,130, does not match the length of theintroducer sheath which already is inserted in the artery, thisintroducer sheath has to be replaced with an introducer sheath havingthe suitable, known length. Since introducer sheaths come in a varietyof dimensions, the first introducer, which is inserted in the artery,must usually be replaced, and a special replacement technique has beendeveloped for this purpose. In one stage, this known replacementtechnique requires that a medically trained person apply manualcompression pressure, and the technique requires further that twoseparate instruments, a guide wire and a dilator, are used.

SUMMARY OF THE INVENTION

[0005] An object of the present invention is therefore to provide animproved method for replacing a first introducer, whose distal end isinserted into a vessel and whose proximal end is outside the skin (orother tissue) of a patient, by a second introducer.

[0006] Another object of the invention is to provide a guide rod, whichis used in the method according to the invention and which replaces theguide wire and the dilator used in the previously known replacementmethod.

[0007] In the method according to the invention, a guide rod is firstinserted into the first introducer, which is in place in the vessel. Thefirst introducer is then removed, thereby leaving only the guide rod inplace. Thereafter, the second introducer is passed over the guide rodand into the vessel, and in a last step the guide rod is removed.

[0008] To not damage the vessel, the guide rod according to theinvention should preferably have a flexible distal portion with a bluntdistal end, while the proximal portion, which has a tapered proximalend, should be stiffer to facilitate the threading of the secondintroducer.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] FIGS. 1-5 illustrate the steps in a replacement procedureaccording to the prior art.

[0010] FIGS. 6-10 illustrate the steps in a replacement procedureaccording to the present invention.

[0011]FIG. 11 shows the guide rod used in the replacement procedureaccording to the present invention.

[0012]FIGS. 12 and 13 show the design and use of a tool for closing apuncture wound.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Before describing the method according to the present invention,a brief description of the method previously utilized to replace a firstintroducer, whose distal end is inside a vessel and whose proximal endextends out of the skin of a patient, with a second introducer, will beprovided. This well-known method may be used, as mentioned above, toreplace the first introducer with a second introducer having a lengththat matches the length of a dilator, which is designed in such a waythat the combination of the dilator and the second introducer can beused as a vessel locator. The method could, however, be used wheneverone wants to change introducer, for instance when a new introducerhaving a larger diameter is needed.

[0014]FIG. 1 illustrates a situation in which a first introducer 1 hasbeen inserted through a puncture hole, which extends from the skin 2 ofa patient, through tissue 3 and through the wall 4 of a blood vessel 5,such that the distal end of the introducer 1 is inside the blood vessel5 while the proximal end of the introducer 1 is outside the skin 2. Thesituation illustrated in FIG. 1 represents a starting point for theconventional method to be described below in conjunction with FIG. 2 toFIG. 5.

[0015] In FIG. 2, the first step of the conventional method is shown. Inthis first step, a guide wire 6 is introduced into the introducer 1until the distal end of the guide wire 6 is well inside the blood vessel5.

[0016] The second step of the conventional method involves the removalof the introducer 1, thereby leaving only the guide wire 6 in place, asis illustrated in FIG. 3. Here, the basic disadvantage of theconventional method is apparent. The diameter of the guide wire 6 ismuch less than the diameter of the puncture hole, and in particular lessthan the diameter of the hole in the wall 4 of the blood vessel 5, whichmeans that blood can flow out from the blood vessel 5. At this stage,external manual compression pressure is usually applied (not shown) inorder to reduce the flow of blood out from the blood vessel 5. Besidesthe problem that it can be difficult to apply enough compressionpressure to completely prevent bleeding from the blood vessel 5, someblood will always flow out from the blood vessel 5. The reason for thisis that the compression pressure cannot be applied during the insertionof a second introducer, since compression of the tissue 3 and the vessel4 would apparently prevent this insertion.

[0017]FIG. 4 shows the third step of the conventional method, in which asecond introducer 7 and a dilator 8 are passed over the guide wire 6until the distal end of the introducer 7 is inside the blood vessel 5.In subsequent steps (not shown), first the guide wire 6 and then thedilator 8 are removed, thereby leaving only the second introducer 7 inplace, as is illustrated in FIG. 5. Here it should be noted that toaccomplish the substitution illustrated in FIG. 1 to FIG. 5, both theguide wire 6 as well as the dilator 8 are needed. It can also bementioned that the removal of the introducer 1, the application of themanual compression and the insertion of the second introducer 7, withthe dilator 8 inserted therein, sometimes can be accomplished by asingle skilful doctor, but often a second medically trained person isrequired.

[0018] The replacement method according to the present invention is nowgoing to be described. Like the conventional method described inconjunction with FIG. 1 to FIG. 5, the present replacement method couldbe used whenever one wants to replace a first introducer with a secondintroducer. The starting point of the present method is the same as forthe conventional method, and in FIG. 6 is illustrated a situation inwhich a first introducer 11 has been inserted through a puncture hole,which extends from the skin 12 of a patient, through tissue 13 andthrough the wall 14 of a blood vessel 15, such that the distal end ofthe introducer 11 is inside the blood vessel 15 while the proximal endof the introducer 11 is outside the skin 12.

[0019] In FIG. 7, the first step of the present method is shown. In thisfirst step, a guide rod 16 is introduced into the introducer 11 untilthe distal end of the guide rod 16 is well inside the blood vessel 15.

[0020] The second step of the present method involves the removal of theintroducer 11, thereby leaving only the guide rod 16 in place, as isillustrated in FIG. 8. Here, one advantage of the present method isapparent. The diameter of the guide rod 16 is equal to the innerdiameter of the introducer 11, and, more importantly, the diameter ofthe guide rod 16 is equal, or almost equal, to the diameter of thepuncture hole in the wall 14 of the blood vessel 15. Furthermore, whenthe introducer 11 is removed, the hole in the vessel wall 14 contractsslightly around the guide rod 16, which means that there will beessentially no flow of blood out from the blood vessel 15. This is anadvantage in itself; and since no external manual compression pressurehas to be applied, one manual operation less has to be executed. Oneoperation less may sound insignificant, but could actually imply thatone medically trained person is saved for other duties, or if only onedoctor is carrying out the operation, that he or she can concentrate onthe insertion of the second introducer.

[0021]FIG. 9 shows the third step of the present method, in which asecond introducer 17 is passed over the guide rod 16 until the distalend of the introducer 17 is inside the blood vessel 15. In a subsequentstep (not shown), the guide rod 16 is removed, thereby leaving only thesecond introducer 17 in place, as is illustrated in FIG. 10. Here itshould be noted that to accomplish the substitution illustrated in FIG.6 to FIG. 10, only one instrument, i.e. the guide rod 16, is needed,which is in contrast to the conventional method in which twoinstruments, i.e. the guide wire and the dilator, were needed.

[0022] The guide rod 16 used in the present method described above isillustrated separately in FIG. 11. The guide rod 16 has a distal portion21 with a distal end 22 and a proximal portion 23 with a proximal end24. The distal portion 21 should preferably be flexible, so that therisk of damaging a vessel during insertion is minimized. To furtherreduce this risk, the distal end 22 should preferably be blunt. Further,the distal portion 21 should preferably be made from a material that canbe pre-bent in such a way that the distal portion 21, after its passagethrough an introducer, resumes its bent shape. The bent shape, whichalso is common for a conventional guide wire, facilitates the insertionof the guide rod 16 into a vessel. To facilitate the threading of anintroducer over the guide rod 16, the proximal portion 23 shouldpreferably be stiff and the proximal end 24 of the proximal portion 23should preferably be tapered. With a stiff proximal portion 23 having atapered end 24 it is considerably easier to thread an introducer overthe guide rod 16, as is done in the method according to the presentinvention, than to thread a dilator over a guide wire, as is done in theconventional method. The guide rod 16 could be made from any suitablematerials, such as plastic or metal, and the distal portion could, forexample, be made in the form of a coil spring. In the FIG. 11embodiment, the guide rod 16 has an outer diameter of 3 French (1 mm) orgreater, such as 6 French, 7 French, 8 French, or more.

[0023] Above, the second introducer, such as the introducer 17illustrated in FIG. 10, has been described as a separate item, to whicha tool for sealing a percutaneous puncture may be connected, as, forexample, is described in the above-mentioned U.S. Pat. No. 6,090,130. Itshould, however, be understood that the method and the guide rodaccording to the present invention equally well can be used in asituation where the second introducer is an integrated part of a toolfor closing a puncture wound. The term “introducer” is therefore hereinmeant to encompass both separate introducers and introducers which arepart of another device. In FIG. 12 such a tool 25 for closing a puncturewound is illustrated. The tool 25 comprises basically a housing 26 and adistal introducer 27, which is fixedly connected to the housing 26. Theintroducer 27 is provided with a first hole 28, which through a canal(not shown in the figure) is in fluid communication with an opening 29provided in the housing 26. This canal can be provided as a longitudinalrecess in the surface of a guide rod over which the introducer 27 isthreaded, or the canal can be provided as a longitudinal, internal holewithin the guide rod.

[0024] In FIG. 13, the introducer 27 of the tool 25 has, over a guiderod 30, been inserted from the skin 31 of a patient, through tissue 32and through the wall 33 of a blood vessel 34. The introducer 27 ispositioned by means of the same positioning operation as was illustratedin FIG. 7 to FIG. 9, and the introducer 27 of FIG. 13 is therefore inthe same position as the introducer 17 of FIG. 9, with the differencethat the introducer 27 is a part of a tool 25 for closing a puncturewound rather than being a separate introducer. In the position shown inFIG. 13, blood can flow into the hole 28 in the introducer 27 through acanal provided in the guide rod and out from the opening 29 provided inthe housing 26, thereby providing a user with a verification that theintroducer 27 is at the correct position with the vessel 34.

[0025] Although the present invention has been described with referenceto specific embodiments, also shown in the appended drawings, it will beapparent for those skilled in the art that many variations andmodifications can be done within the scope of the invention as describedin the specification and defined with reference to the following claims.It should, for example, be clear that the method and the guide rodaccording to the present invention are not limited to be used in bloodvessels, but could be used in any vessel when a first introducer has tobe replaced with a second introducer. As another example, the guide rodcould be provided with a measurement scale, for example, in the form ofcentimeter or millimeter marks, that provide a user with an indicationof how far the guide rod is inserted into the introducer.

What is claimed is:
 1. A method for replacing a first introducer, whosedistal end is inside a vessel and whose proximal end is outside the skinof a patient, with a second introducer, said method comprising the stepsof: inserting a guide rod into the first introducer until the distal endof the guide rod is inside the vessel, removing the first introducer,thereby leaving only the guide rod in place, passing the secondintroducer over the guide rod until the distal end of the secondintroducer is inside the vessel, and removing the guide rod, therebyleaving only the second introducer in place.
 2. A guide rod to be usedin the method according to claim 1, wherein the guide rod comprises aflexible distal portion and a stiff proximal portion.
 3. A guide rodaccording to claim 2, wherein the distal portion has a blunt end.
 4. Aguide rod according to claim 2, wherein the proximal portion has atapered end.
 5. A guide rod according to claim 2, wherein the distalportion can be pre-bent in such a way that it resumes its bent shapeafter having passed through the first introducer.
 6. A guide rodaccording to claim 2, wherein a diameter of the guide rod isapproximately the same size as a puncture in a wall of the vessel.
 7. Aguide rod according to claim 2, further comprising a measurement scale.8. A guide rod according to claim 2, wherein the surface of the guiderod is provided with a longitudinal recess.
 9. A guide rod according toclaim 2, wherein the guide rod is provided with a longitudinal, internalhole.
 10. A method for replacing a first introducer, whose distal end isinside a vessel and whose proximal end is outside the skin of a patient,with a second introducer, said method comprising the steps of: insertinga guide rod into the first introducer until the distal end of the guiderod is inside the vessel, removing the first introducer, thereby leavingthe guide rod in place, passing the second introducer over the guide roduntil the distal end of the second introducer is inside the vessel, andremoving the guide rod, thereby leaving the second introducer in place.11. A guide rod for insertion of a new introducer in replacement of afirst introducer such that a distal end of said new introducer reachesthrough a puncture hole in a vessel wall to be positioned inside thevessel, while a proximal end of the new introducer being located outsidethe skin of a patient, the guide rod having a distal portion with adistal end and a proximal portion with a proximal end, said guide rodbeing characterized by a stiff proximal portion and a flexible distalportion.
 12. The guide rod of claim 11, wherein the distal portion has ablunt end.
 13. The guide rod of claim 11, wherein the proximal portionhas a tapered end.
 14. The guide rod according to claim 11, wherein thedistal portion can be pre-bent in such a way that it resumes its bentshape after having passed through the first introducer.
 15. The guiderod according to claim 11, wherein a diameter of the guide rod isclosely adapted to the inner diameter of the first and new introducers.16. The guide rod according to claim 11, wherein the diameter of theguide rod is approximately the same size as a puncture in the wall ofthe vessel.
 17. The guide rod according to claim 11, further comprisinga measurement scale.
 18. The guide rod according to claim 11, whereinthe surface of the guide rod is provided with a longitudinal recess. 19.The guide rod according to claim 11, wherein the guide rod is providedwith a longitudinal, internal hole.